Snap acting switch



March 22, 1960 H. J. TYLER SNAP ACTING SWITCH 7 Sheets- Sheet 1 FiledJan. 13, 1958 Marsh 22, 1960 H. J. TYLER 2,929,891 SNAP ACTING SWITCHFiled Jan. 13, 1958 7 Sheets-Sheet 2 March 22, 19% H. J. TYLER SNAPACTING SWITCH 7 Sheets-Sheet 3 Filed Jan. 13, 1958 March 22, 1966 H. J.TYLER sm ACTING SWITCH 7 sheets sheet 4 Filed Jan. 13, 1958 March 22,1960 H, J, TYLER 2,929,891

SNAP ACTING SWITCH Filed Jan. 1:, 1958 7 Sheets-Sheet 5 arch 22, 196@ JTYLER 2,929,891

SNAP ACTING SWITCH Filed Jan. 13, 1958 7 Sheets-Sheet 6 March 22, 1960H. J. TYLER SNAP ACTING SWITCH '7 Sheeis-Sheet 7 Filed Jan 13, 1958United States Patent SNAP ACTING SWITCH Hugh J. Tyler, Jeannette, Pa.,assignor to Robertshaw- Fulton Controls Company, Richmond, Va., acorporation of Delaware Application January 13, 1958, Serial No. 708,497

15 Claims. (Cl. 200-67) This invention relates to a snap actingmechanism and more particularly to a miniature heavy-duty snap actingswitch in which a force is applied to an actuatingmember in onedirection to move a contact carrier in an opposite direction with a snapaction.

An object of this invention is to move the free end of an actuatedmember in a snap acting mechanism in two directions.

This invention has another object in that the free end of an actuatedmember in a snap acting mechanism is movable in a direction opposite toan applied force and in a direction substantially perpendicular to theapplied force.

This invention has a further object in that the applied force in a snapacting switch is utilized to maintain substantial contact pressure untilthe instant of snap over and to produce a contact wiping action.

It is another object of this invention to apply a wiping action force onthe movable contact of a snap acting switch without interfering with thecontact pressure force.

It is another object of this invention to produce a wiping actionbetween the mating contacts in a snap acting switch by transversemovement of the movable contact arm.

An additional object of this invention is to construct a snap actingminiature switch that is simple, economical, compact, and capable ofmaintaining a minimum switch differential while being responsive to asmall operating force.

In carrying out this invention, the actuating member and the actuatedmember of a snap acting mechanism have free ends with portions that areinterconnected by resilient means so that movement of the actuatingmember by an applied force moves' the resilient means beyond anovercenter position causing the free end of the actuated member to movewith a snap action in a direction opposite to the applied force. Anoperable connection between portions of the other ends of the actuatingmember and the actuated member causes the actuated member to move inresponse to the applied force and supply a wiping action to its free endin a direction substantially perpendicular to the snap action.

Other objects and advantages of this invention will become apparent fromthe following description taken in connection with the accompanyingdrawings, wherein:

Fig. 1 is a longitudinal section view of a snap acting switch embodyingthis invention showing the switch contacts in their normal position witha minimum operating force;

Fig. 2 is similar to Fig. 1 but showing the position of the parts withan increased applied force;

Fig. 3 is similar to Fig. 1 but showing the position of the snap actingmechanism as it moves through an overcenter position;

Fig. 4 is similar to Fig. 1 but showing the position of the contactsafter the snap acting mechanism has been moved through its overcenterposition;

ii 2 2,929,891 Patented Mar. 22, 1960 Fig. 5 is similar to Fig. 2 butshowing the contacts in their opposite mating position;

Fig. 6 is an exploded perspective view of the snap acting elements shownin Fig. l;

Fig. 7 is a longitudinal section view of a modification of thisinvention;

Fig. 8 is a longitudinal section view of another modi fication of thisinvention;

Fig. 9 is a longitudinal section view of another modification of thisinvention;

Fig. 10 is a longitudinal section view of another modification of thisinvention;

Fig. 11 is an exploded perspective view of the snap acting elementsshown in Fig. 10;

Fig. 12 is a longitudinal section view of another modification of thisinvention;

Fig. 13 is a longitudinal section view of another modification of thisinvention;

Fig. 14 is an exploded perspective view of the snap acting elementsshown in Fig. 13;

Fig. 15 is a longitudinal section view of another modification of thisinvention;

Fig. 16 is an exploded perspective view of the snap acting elementsshown in Fig. 15;

Fig. 17 is a longitudinal section view of another modification of thisinvention; and

Fig. 18 is an exploded perspective view of the snap and comprises a topmember 12 (Fig. 17) secured to as base member 14 by any suitable means(not shown). A"

pair of fixed contacts 16 and 18 are mounted in spaced parallel relationon the base member 14 and extend through a wall thereof to beelectrically connected to conventional lead wires. Movable contact means20 comprising a pair of contacts. are secured to opposite sides of acontact pressure lever arm 22 adjacent its free end which is disposed inthe space between fixed contacts 16 and 18 for movement therebetween.

The contact carrying arm 22 is a generally rectangular strip made ofgood conducting material, such as copper or the like. As is illustratedin Fig. 6, arm 22 comprises a mounting portion 24, a vertical offsetportion 26 extending downwardly therefrom and a rigid actuated portion28 having a rectangular opening 30. A shoulder por tion shown as anapertured tab 32 extends into opening 30 from the end thereof which isadjacent the movablecontact 20. The mounting portion 24 is secured tobaseposite the fixed contacts 16 and 18 and is adapted to beelectrically connected to a conventional lead wire,

The inner end of mounting portion 24 overlies a small ledge 34 oftapering cross-section formed as an integral extension of base member 14and defines an axis of rotation for a purpose to be describedhereinafter.

As is illustrated in Fig. 6, an inflexible strip 36 in the form of agenerally inverted U-shaped actuating lever comprises a pair of spacedparallel arm members 38 being joined at one end with a downwardlyextending connecting portion 40 and having at their opposite ends a pairof downwardly extending leg members 42. The extremity of each leg member42 is provided with a V-shaped bearing notch 44 that serves as a pivotpoint. It is to be understood that reference to a pivot point is to be'construed as including a pivot axis for the purposes of this invention.The length of the actuating lever 36 is smaller than the strip 22 sothat the pivot point 44 is movable through the confines of therectangular opening 30 relative to the strip 22,- however, the length issuch that the pivot point'44 extends slightly rearward of apertured tab32 away-from the movable-contact- 20. The connecting portion 40 isfastened to the vertical offset portion 26 of the strip 22 by anysuitable means, such as rivets 46, to constitute a flexible hingeconnection, indicated generally at 48, betweenthe adjacent ends of strip22- and strip 36.

A rigid toggle link, indicated generally at 50in Fig. 6, comprises apair of spaced parallel arm members 52 having a pair of knife edges 54on one end andbei'ng joined at the opposite end by an arcuate portion 56which has an ap ertured tab 58 on its inner periphery extending betweenand parallel to the arms 52. Toggle link stop means 60 formed on theouter periphery of arcuate portion 56 includes a pair of oppositelyextending vertical members 61 and 62 having a pair of lugs 63 and 64extending perpendicularly of their respective ends. The vertical members61 and 62 are inclined slightly inwardly from the vertical to convergetoward the plane otthe arms ndthe ab58. v f In order to make an operableconnection betweenthe re ends. Q he. t ip 2. an re li nt me s nv theterm of a tension coil spring 66jis incorporated with the toggle link50. Qne endro'f; coil spring .6 6 is. hooked through the apertured' tab32 on thestrip' 22an'dits opposite end is hooked through the aperturedtab 58 on the toggle link 50. The size of the toggle link 50 is smallerthan the size of the rectangular opening 30in which link 50 movesrelative to the strip 22. The linkSii is disposed within the confines ofthe rectangular opening 30 with the knife edge 54 on one end engagingthe V- shaped notches,44 on the strip 36 for pivotalmovement therein andwith the stop lugs 63 and 64 on the other end engaging the respectivelower and upper surfaces (Figs. Land-4) of that part of strip 22 whichdefines the corresponding end of rectangular opening 30.

flnthje operation of the device illustrated in Fig. 1, an op;atingforce, indicated by the varrow 68, is applied to the actuatinglever 36. The arrow 68 is not to be construedas a vector representingmagnitude and direction bn't, only as an indication of thedirection ofthe operating fprcje. A conventional push button and cross bar (notshown) engaging lever arms 38 may be utilizedfor this purpose as well asvarious other arrangements well known to those skilled in the art.- Thespring force of the yieldable. spring .66 is exertedonthe free endoftheactuated -St'rip22 whereby movable contact 20 is pulled down with ac'ontact force into mating engagement with the lower xed contact 18. Thespring force isalso exerted on toggle ,link 50 tending to rotate thesameina counterclockwise, direction which=rotation is prevented by theshaping 63 engaging an edge of the actuated strip 22 andthus increasingthe contact pressure force.

Fig 2 illustrates the position of the operating elements when theoperating force has been increased. Such an increasecauses the pivotpoint 44 on lever 36 to move downwardly toits critical position where itlies in a plane-coincident with the plane defined by the apertured tab32 and theend of coil spring. 66 hooked thereon. At this criticalposition, the spring force tending to rotate toggle link 50 is zerobecause the longitudinal axis of the coil spring 66 is in alignmentbetween and disposed in a plane defined by the parallel toggle arms 52.

However, the end of coil spring 66 which is hooked on toggle-tab 58 isdisposed in a plane beneath the planeof ,pivot point'44 so thatthe'movable contact 20 is still being pulled downward into engagementwith fixed contact 18 and the contact pressure force remainssubstantially unchanged from the conditions existing in Fig. l. Thedistance traversed by pivot point 44 from Fig; 1 to Fig. 2-does notaffect the contact force sincethe-tension of coil springv 66 is notvaried. Because of the rigidity of toggle link 50 any force exertedthereon by lever-36' at the pivotal connection therebetween istransmitted to theastop means 60 where the horizontal cemponentofapaassi r such force urges the vertical stop member 61 into engagement with the edge defining the correspondingend of rectangularopening 30 in strip 22 and the vertical component further urges stop lug63 into engagement with strip 22 to add to the contact pressure force.

A further slight increase in the operating force 68 causes toggle link50 to rotate in a clockwise direction to the position shown in Fig.4moving rapidly through the dead center position shown in Fig. 3. In Fig.3, which represents the position of the elements at the instant of snapover, the contact force between contacts 18 and 20 is zero because thelongitudinal axis of coil spring 66, the toggle arms 52, the pivot point44. and the apertured tabs 32 and 58 are disposed on the same horizontalplane. During movement of lever 36 from the position shown in Fig. 1 tothat shown in Fig. 3, a slight movement of strip 22 to the left iseffected by the flexible hinge connection 48 so that movable contact 20is provided with 'a wiping action relative to the-fixed contact-18. qMovement of'toggle link 50 through the position shown in Fig. 3 andthe-simultaneous movement of the coil spring 66' through its over centerposition causes themovablecontact ZDIon'thefree end ofstrip 22 tomovewith. a snap action ina direction opposite to the direcnon of theactuating-force exerted by lever 36. As isshown in Fig 4, the, toggleconnected end of coil spring 66 is disposed above its actuated'stripconnected end so that'the spring force exerted on the free end ofstrip22 has a direction that is reversed relative to Fig. 1 and themovablecontact 20 is held in engagement with the upper fixed contact 16.

The applied force 68, which is increased to effect the snap action ofmovable contact 20, also provides the movable contact 20 with a wipingaction by causing the flexible hinge 48 to rotate clockwise about theaxis of rotation 34. This wiping action produces a self-cleaning efiecton the contact surfaces and is also effective as a shearing actiontobreak a weld'betweencontact surfacesthat may have been formed during aprevious contact making action. In the. event a weld, occurs, the wipingaction is prevented until the force tending to rotate the flexible hinge48 about. thev axis of rotation 34' is sufitciently great toshear thewelded'contact surfaces.

Ityis to be understoodthat the snap-acting elements inVFig 4, could,bfedetainedv in sucha position andv the. applied force 68 removed from theactuator lever 36 However, in describing this invention, the snap-actingelements are returned to their original position shown in. Fig. 1 inresponse-to the decrease of applied force 63 as would occur inathermostatic device. Accordingly, the operationof the snap-actingelements then proceeds in reverse to the above described operation forFigs. 1-4; thus, when the operating force .is initia'lly decreased, thepivot point 44' returns toits critical position as illustrated in Fig.5, which is similar to Fig.2 except that the elements. are reversed.Furtherdecrease in the operating force 68 causes the coil spring 66 tomove from its 7 over center position in Fig. 5 through its dead centerposition shown in Fig. 3 to. its original position shown in Fig. I withthe movable contact 20 moving with a snap action fromthe upper fixedcontact 16 to the lower fixed contact 18. v

Inthe following description of the various modifications of thisinvention, the same reference numerals will be used to designateidentical parts and reference numerals with the addition of will be usedto designate similar parts of the differentmodifications. Thus, in Fig.7, the movable portion of a contact carrying arm 122 is provided with arectangular opening that is longer than the opening 30 in the' previousmodification. An inflexible actuating lever 136 has a pair of downwardlyextending leg members 142, the extremities of which are connected by aperpendicularly disposed cross tab 143; A' toggle link diifersfrom thepre} viously described link 5 0by having a larger length for open .v-sha ped notch 155 on the free end of each of its pair 'of parallel armmembers 152 (only one being shown). A tension coil spring 166 cooperateswith toggle link 150 to form an operable connection between the actuatedand actuating members 122 and 136. One end of co'il spring 166 is hookedon the tab 143 of the inflexible lever 136 and its opposite end ishooked through the apertured tab 58 on the toggle link 150. The V-'shaped notch 155 on the free end of each arm 152 serves as a pivot pointfor the toggle link 150 and engages the strip 122 at that portiondefining the forward edge of the rectangular opening 130.

The modification in Fig. 7 operates in substantially the same manner asdescribed above for Fig. 1. It is to be'noted, however, that the leverconnected end of the yieldable spring 166 is movable downward inresponse to-the applied force 68 on-the actuating lever 136. Thus,

the pivot point 155 on the toggle link 150 does not move untilsnapaction occurs. Furthermore, the stop lugs 63 and 64 are located agreater distance from the free end of the flexible strip 122-s'o-thatthe pressure exerted against the strip 122 by the stop lugs 63 and 64does not reduce the contact force between movable contact 20 and itsmated one of the fixed contacts 16 and 18.

Another modification shown in Fig. 8 includes a fiat inflexible actuator236 having one end pivotally mounted at 235 and a pair of downwardlyextending legs 242 (only one being shown) on the other end, theextremities of which are provided with V-shaped bearing notches 244which serve as a pivot point. A return spring 237 is mounted incompression between an internal wall of casing 10 and the undersurfaceof actuator 236. The contact carrying arm 222 is similar to the arm 22in Fig. 1 except that the offsetting portion 226 extends verticallyupwardly from the mounting portion 24 which islocated in a plane belowthe plane of the fixed contact '18. A flexible hinged connection 48 isformed by a ibell crank lever 270 which is pivoted at 272 and has onearm 274 engaging the undersurface of actuating ilever 236 and anotherarm 276 engaging the vertical portion 226 of arm 222. As is illustratedin Figs. 1-3, -.the flexible hinged connection 48 causes the wipingaction 'of movable contact 20 to be toward the left, whereas "theflexible hinged connection 48 in Fig. 8 causes the wiring action to betoward the right.

' Operation of the modification illustrated in Fig. 8 is reflected by aforce 68 applied to actuating lever 236 tcausing the same to rotateclockwise about pivot 235 so rthat the pivot point 244 is movable in thesame manner :as previously described in connection with Fig. 1.Moveintent of lever 236 also causes bell crank lever 270 to rottatecounterclockwise so that the flexible hinged connection 248 rotatesclockwise about the axis of rotation 34. The results obtained'by thesnap acting switch in Fig. 1 are also obtained by the snap acting switchin Fig. 8 which utilizes separate elements that are readily connectedinto a thermostatic element lever system. Furthermore, this modificationis readily adaptable for use with separate elements so that the wipingaction force could be applied directly to contacts 16 and 18 forslidingthe same relative to contact 20.

Another modification is shown in Fig. 9 wherein an inflexible actuatinglever 336 is a generally U-shaped solid strip having a connectingportion 40 on one end and a leg member 342 on the other end. A tab 343is bent substantially perpendicularly from the free end of the leg 342.A contact carrying arm 322 is provided with a rectangular opening 330which is smaller than the previously described opening 30 in Fig. 1. Anoperable connection between the free ends of the strips 322 and 336includes a generally U-shaped rolling spring 366 having V-shaped bearingnotches 365 and 367 on respectiveends of its leg portions; the notch 365receives the tab 343 on the strip 336 to serve as a pivot point thereforand the notch 367 engages that portion of'strip' 322 which defines theforward edge of the rectangular opening 330. With spring 366 mounted incompression, the movable contact 20 is moved with a snap action when theapplied force 68 causes the pivot point 365 to move downwardly below theplane of the notch 367. A wiping action of the contact 20 is effected bythe strip 322 as previously described by means of the flexible hingedconnection 48 which may also be utilized to function as a return springwhen the applied force 68 is removed.

Figs. 10 and 11 illustrate another modification of this inventionwherein the toggle link and resilient means move between the actuatingand actuated strips, which permits manufacture of a very narrow switchmechanism for a miniature housing. A contact carrying conductor strip422 (Fig. 11) has a free end carrying the movable contact means 20 and amounting portion 24 extending perpendicularly from a vertical offsettingportion 26, as previously described in connection with Fig. 1. Inaddidition, solid strip 422 comprises a central horizontal portion 428with legs 427 and 429 extending vertically upwardly from opposite ends;vertical leg 427 terminates in an outwardly extending horizontal portion431 which is joined to the vertical offsetting portion 26 and vertical.leg 429 terminates in an oppositely outwardly extending horizontalportion which forms the free end of strip 422 1 tending leg members 442at its opposite end. The extremities of legs 442 are provided withV-shaped bearing notches 444 that serve as a pivot point.

A toggle link 450 is similar to link 50 in Fig. 1 except that stop means460 comprises relatively short vertical members 461 and 462 havingedges463 and 464, respectively, to serve as stop lugs. The arm members 52 arejoined at one end to a straight portion 456 having a straight edge fromwhich the vertical members 461 and 462 extend in opposite directions toform a T-shape. counterclockwise rotation of toggle link 450 about itspivot point 44 in the position shown in Fig. 10

is prevented by stop edge 464 engaging the actuated strip 422; clockwiserotation of toggle link 450 in a position reversed to Fig. 10 isprevented by stop edge 463 engaging the actuating strip 436.

During the operation of the device shown in Figs. 10 and 11, the pivotpoint 444 is moved downward in responseto the applied force 68 to thecritical point where pivot point 444 is aligned with apertured tab 432.A further slight increase in the applied force 68 actuates the togglelink 450 in a clockwise direction about the pivot point 444 causing thecoil spring 466 to move rapidly through a dead center position to anover center position in which the stop edge 463 engages the undersurfaceof actuating lever 436. Because of the flexible hinge 48, the appliedforce 68 which causes the movable contact 20 to be moved in a verticaldirection with a snap action, also causes the movable contact 20 to bemoved in a horizontal direction with a wiping action. The vertical forceis the vertical component of the force exerted by spring 466 and thehorizontal force is the horizontal component of the force exerted by theflexible hinged connection 48 as described pre iously.

Another modification illustrated in Fig. 12 comprises a narrow switchmechanism and reverses the positions of a toggle link 550 and coilspring 566 from that described in Fig. 10, whereby the lever-connectedend of coilispring 566 is movable relative to the pivot point I folthetoggle link 550. A contact carrying strip 522 verted U-shaped solidstrip has the extremity of its' leg member .542 bent outwardly into atab-543. The toggle link 55% is constructed in the same shape as link450 in Fig. 11. Yieldable means in the form of a tension coil spring 566has one end hooked around tab 543 on the actuating strip 536 and anopposite end hooked through the apertured tab 58 on the toggle link 550.

The operation of the switch shown in 12 is similar to that previouslydescribed in connection with Fig. 7

except that the stop means .560 alternately engages the.

actuated and actuating strips 522 and 536 as determined by the alternateengagement of movable contact 26 with fixed contacts 16 and 18,respectively.

:Another modification of this invention is illustrated in Figs. '13 and1'4 wherein the actuated strip is disposed within the confines of theactuating strip. The actuated contact pressure lever arm 622 has a freeend carrying I the movable contactmeans 20 and a mountingportion 24extending perpendicularly from a verticalofisetting portion 26, aspreviously described in connection with Fig. l. The actuated strip622includes a rigid actuatedportion 628 provided with a rectangular opening630 that is longer than the opening 39 in Fig. 1. An inflexibleactuating lever 636 comprises a connecting portion 40 and a pair of.spaced parallel arm members 638 extending from theside edges thereof. Asis illustrated in Fig. 14, the parallel arm members 638 are disposed inan edgewise manner, the upper edges of which are provided withacut-outportion' 639 along their upper edges; ,The free ends of arms 638have upwardly extending leg members 642, each of Which'is provided witha V-shaped bearing notch 644 that serves as a pivot point. The upperedges of spaced arms 638 are'notched at 641 to receive a bridge member663 which applies an operatingforce to the actuating lever 636.

A toggle link 650 comprises a pair of spaced parallel arms 652slopingdownwardly from the forward edge of a straight portion 656 andterminating in knife edges 654. Toggle link stop means 669 has avertical member 661 sloping downwardly from the rearward edge of thestraight portion 656 and being disposed for movement within the slot639. The ends of member 661 are provided with upper and lower crosspieces which serve plate has adownwardly .slopingsection 702 so thatthe. two horizontal portions 701 and 703 are .otr'setffromcneh j other.The rigid actuated strip 728 is secured 0.110.15 zontal portion '703byany suitable means such as rivets, The vertical offsetting portion 726is disposed along the:

side of strip 728 and is secured to an adjacent arm 73B of the actuatinglever 736 by any suitable means :suh

as rivets. The connecting end 740 of the lever 738 is horizontallydisposed'parallel to the mounting end 724 and is secured thereto by anysuitable means such as rivets. In this modification, rigid portion 728,the battle up plate, offsetting portion 726, the lever connecting end740, and the mounting portion 724 are all made of good conductingmaterial, such as copper or the like.

As is illustrated in Fig. 16, a toggle link 750 is similar to :link 650in Fig. 14 and its vertical member 761 of the stop means is bentinter-mediate its ends-so that the upperstop-lug 763 and-lower stop lug764 are in .convergent relation.

The position of the operating elements in Fig. 1-5 :are shown tocorrespond to the position illustrated inFig. 1; the operation of themodification illustrated in iFigsilS. and 16 is similar to that of themodification inQFig. 13 and the-flexible hinge connection 48in bothsuchmo'di fications operate in a manner similar to that described inconnection with Fig. 1.

Another modification is illustrated in Figs. 17 -and.;1 8 wherein thetoggle link and resilient means move between narrow actuating =andactuated strips, which pen mits manufacture of a very-narrow and flatswitchsmehanism for a miniaturehousing. A contactcarrying-con.-ductorstrip 822 has a free'end carrying the movablecontact means 20 anda mounting portion 24 extending 828 with legs 827 and 829 slopingupwardly from oppo-,; site ends thereof; leg 827 .is joined to theofisetting portion26 and leg829 is joined'to the horizontal portion asstop lugs; only lower lug 664 is shown in Fig. 14

and the upper stop lug 663 is similar to stop lug 763 in Fig. 16.

*Agenerally L-shape'd back-up plate has a vertical portion 602 afiixedto the rear of vertical oifsetting portion 26 and a horizontal portion603 with a facet 66 A return spring 637 encircles horizontal portion 603and is mounted in compression between the facet 604 and a circular wallportion of base '14.

Operation of the modification illustrated in Fig. 13 is similar to thatpreviously described in connection with Fig. 1, and the positions of theoperating elements are shown to-correspond to the position illustratedin Fig. 2.

In Fig. 13, the upper stop lug engages the edges of strip plate by"means -:ot horizontal: plate 701. The backupwhich forms the free endof-strip 822-containing the movable contact means 20. An apertured tab'832-is formedas apart of leg 829 and lies'in a plane-coincidentiwiththe free-end of strip 822. The legs 827 and 829 cooperate with thecentral horizontal portion 828 to form a longitudinal recess in theactuatedjstrip 822. The solid horizontal portion 828, as well as'litscorresponding part'in all previous -modifications,.'2is

formed of any suitable 'material to prevent buckling.

thereof and in Fig. 18, side-flanges 833 are integrally formed on eachside of centraliportion 828and theitwo legs 827 and 829 in order toenhance the rigidity thereof.

An actuating lever 836' has a pair-of spaced parallel arms 838 joined atone end witha downwardly :ex-

tendingconnecting portion 40 and bent at an opposite. end. to formdownwardly extending leg 'members 842.

The extremity of each leg member 842 is provided'with a V-shapedbearingznotch that serves as a pivot point 844. The actuating lever 836'is also provided in a phajection841 which is engaged by a plunger868-fortapplyingan operating forcethereto.

A toggle link 850 is similar to link 4'50 shown-air! Fig. 11 but hasbeen simplified by positioning an aperture 858 in the straight portion856 and utilizing the 'u-pper andlower edges thereof as upper and lowerstoplugs 863 and 864, respectively. Thus, counterclockwise rotationoftoggle link 850 about its pivot point 844 in -the position shown in Fig.17 is prevented by stop edge 863' engaging the central horizontalportion 828ofstr ip 822; clockwise rotation oftoggle link 850 inapo'sitidn reversed toil-" ig. 10- is prevented by stop edge864--engaging the actuating lever 836.

The-flexible hinge connection.48=is,providdwithlm Lashaped backpp platehaving .a 'verticahportion 802 affixed to the rear of offsettingportion26 ands-horizontal Inasmuch as various changes may be made in the arrangement and combination of parts and in the details of'theconstructions herein disclosed, it is intended that the foregoingdescriptions and drawings be interpreted as illustrative and not in alimiting sense.

I claim:

' 1. In a snap acting mechanism, the combination comprising a striphaving first and second oppositely disposed ends, means includingresilient means and forming an operable connection with said stripadjacent the first end thereof, actuating means operatively connected tosaid first mentioned means whereby said resilient means is movable inone direction past a dead center position causing movement of the firstend of said strip with a snap action, and the second end of said striphaving a portion operably fastened to said actuating means to form aflexible connection therebetween whereby the first end of said strip iscaused to move substantially perpendicular to the snap action movement.

' 2. In a snap acting mechanism, the combination comprising an actuatedelement having a mounting end and a movable end, an actuating elementhaving opposite ends respectively disposed adjacent the ends of saidactuated element, movable means including resilient means and having onepart operatively connected to one of the ends of said actuating elementfor movement thereby and having another part operatively connected tosaid actuated element adjacent the movable end thereof whereby movementof said first mentioned means by said actuating element causes saidresilient means to pass a dead center position to move the movable endof said actuated element in one direction with a snap action, and themounting end of said actuated element having a connecting portionoperably fastened to the other end of said actuating element wherebymovement of the same causes the movable end of said actuated element tomove in a direction substantially perpendicular to the direction of suchsnap action.

3. A snap acting mechanism comprising, an actuated arm having a mountingend provided with a flexible connecting portion adjacent the mountingend and having a free end provided with a shoulder portion adjacent thefree end, an actuating lever having a connecting end disposed adjacentthe said oifset portion and a free end provided with a pivot means,means including spring means and having one part operatively connectedto the said shoulder portion and an opposite part operatively connectedto the said pivot means, said lever being movable when force is appliedthereto to move the said pivot means beyond a critical position wherethe pivot means is in alignment with the said shoulder portion so thatsaid spring means causes the free end of said arm to move with a snapaction in a direction opposite to the force applied-to said lever, andthe connecting end of said lever being fastened to the flexibleconnecting portion of said arm so that when force is applied to saidlever the free end of said arm is also moved in another direction.

4. A snap acting mechanism comprising, an actuated arm having a fixedend with an ofisetting portion and a free end with a shoulder portion,an actuating lever having a connecting portion on onerend and pivotmeans on an opposite end, a toggle member having connecting means on oneend and pivot means on an opposite end engaging the pivot means on saidlever, spring means mounted in tension between the connecting means onsaid toggle member and the shoulder portion on said arm, said leverbeing movable by an applied force to move both pivot means beyond acritical position where theconnecting means and pivot means on saidtoggle memher are in alignment with the shoulder portion on saidarm sothat said spring means causes the free end of said arm to move with asnap action in a direction opposite to the force applied to said leverand cause the said one end of said toggle member to swing simultaneouslywith the free end of said arm, and the ofisetting portion of said armbeing operably fastened to the connecting portion on said lever wherebymovement of the same causes move-' ment of the free end of said arm in adirection substan' tially perpendicular to the snap action thereof.

5. The combination as recited in claim 4 wherein saidtoggle member isprovided with stop means on the said one end thereof to limit the swingof said toggle member.

6. In a snap acting mechanism, the combination com-' prising; anactuating arm having a downwardly extendingf connecting portion on oneend and a downwardly extend-- ing leg means on the other end, pivotmeans disposed on. the extremity of the leg means; an actuated memberhail ing a mounting portion on one end, a'mo'vable portion force isexerted on the free end thereof; said arm being movable by an appliedforce to move both pivot means beyond a critical position for swingingsaid toggle link and causing the spring force exerted on the free end ofsaid actuated member to reverse its direction with a snap action; and,the connecting portion of said arm being operably secured to thevertical offsetting portion of said actuated member forming a flexiblehinge whereby the" same force applied to said arm causes the free end ofsaid actuated member to move in another direction.

7. In a snap acting mechanism, the combination com prising; an actuatingmember having a pair of spaced parallel arms, a connecting portionextending downwardly, from one end of said arms, and a leg memberextending downwardly from each of the other ends of said arms, a crosstab joining the extremities of each leg member; an actuated memberhaving a mounting portion, a movable portion and a vertical offsettingportion therebetween, a shoulder portion on said movable portiondisposed inwardly from the free end thereof; a toggle link having anapertured tab adjacent one end and V-shaped bearing means on an oppositeend in engagement with the shoulder portion on said actuated f memberand cooperating therewith to form pivot means; a coil spring mounted intension between the apertured tab on said toggle link and the cross tabon said actuating member whereby a spring force tends to rotate saidtoggle link about said pivot means; stop means on said toggle linkengaging said actuated member to prevent the rotation of said togglelink whereby the spring force is exerted on the free end of saidactuated member; said actuating member being movable by an applied forceto move the cross tab beyond a critical position where it is in 'align-.ment with said pivot means causing said toggle link to.- swing aboutsaid pivot means whereby the spring force exerted on the free end ofsaid actuated member reverses its direction with a snap action; and theconnecting POP. tion of said actuating member being operably secured tothe vertical ofisetting portion of said actuating member causing thefree end of said actuated member to move in another direction inresponse to the applied force on said actuating member.

8. In a snap acting switch, the combination comprising an actuatinglever being pivotally mounted at one end and having a leg memberextending downwardly from II an 6pposite end, pivot means disposed onthe extremity of 's'a'id legmember, an actuated member having'a mountingportion, an ofisetting portion extending fromthe mounting portion and amovable portion extending from the offsetting portion to a movable end,an operable connection including a toggle link and a coil springconnected thereto mounted between said lever and said actuated memberwith the toggle link engaging said pivot means 'on'said'lever andthecoil spring connected to the movable portion of said-actuated memberwhereby a spring force is exerted on the movable end of said actuatedmember, said lever being movable by an applied force causing saidoperable connection to move the free end of said actuated member with asnap action,-and a bell crank lever p'ivotally mounted with one armbeing.

movable by said actuating lever and another arm operable to bias theoffsetting portion on said actuated member whereby the applied force onsaid actuating lever pivotssaid-bell crank lever to move the free end ofsaid actuated-member with a wiping action.

9.-ln a snap acting mechanism, the combination comprising an actuatingmember and an actuated member dispbsed insuperimposedrelation, each ofsaid members having connecting portions on opposite ends, a U-shapedrolling spring mounted in compression between the conn'etingportions onadjacent ends of said members whereby a force appliedto-said actuatingmember moves said spring through a dead center position subjecting saidactuated member to a snap acting'force, the other connecting portion ofsaid actuated member comprising a flxibleportion, and the otherconnecting portion of said actuating member being secured to saidflexible portion whereby the same force applied to said actuating membersubjects said actuated member to a wiping force.

-1 0. In a snap acting mechanism, the cornbinationcomprising anactuating member having a connecting portion on one end and pivot meanson an opposed end, a recs'sd actuated member having a movable end and anid'unting portion on an opposite end, a vertical ofisetting portionextending downwardlyfrom said mounting por tion, a substantiallyU-shaped portion extending between themovable end and the offsettingportion, an apertured tab extending inwardly from the movable end, atoggle link having an apertured tab adjacent one end and pivot means onan opposed end engaging the pivot means on said actuating member, a coilspring mounted in tension with"o'pposed ends secured respectively in theapertured tabs on said toggle link and said actuated member whereby asprin force tends to swing said toggle link about its pivotm'ea'ns, stopmeans on said toggle link engageable with th'e U-s'h'aped portion ofsaid actuated member to reven swingin of said'toggle link'whereby thespring fo'r'e 'istransmitted to the movable end of said actuated "r,said actuating member being movable by an "for'ce'to move both pivotmeansbeyo'nd an aligned p ion with "the apertured tab on said actuatedmember causing said 'toggle link to swing about its pivot meanstd'apositi'on'where said stop means engagessaid actuating member wherebythe spring force transmitted to "the'rnovable end of said actuatedmember reverses its direction with a snap action, and the connectingportion of said actuatingmemberbeing operably secured to the ofisettin'gpbr'tion of said actuated member forming'a flexible hin'g'e' whereby themovable end of said actuated'member moves a -wiping "action in responseto the force applied to actuating member.

sa i

1ft. In a snap acting mechanism, the c'ombinationcomprising-an actuatingmember having a connecting portion on one "end and a connecting tab onan opposite end, a'reeessed-actuated member having 'a movable end and amounting 'portion 'on anopposite end, a vertical'otfsettin'g portionextending downwardly from said mountingportion, a substantially U-shapedportion extending between the mov'ableend and the offsetting portion,pivot means extending inwardly from the movable end of said actuatedmember, a toggle link having an apertured tab adjacent one end and pivotmeans on an opposed end engaging the pivot means on said actuatedmember, a coil spring mounted in .tensi'on'with opposed ends securedrespectively to the apertured tab on said toggle link and the connectingtab on said actuating member whereby a spring force tends to swing saidtoggle link about its pivot mean's, stop means on said toggle linkengageable with said actuating member to prevent swinging of said togglelink whereby the spring force is transmittedto'the movable end of saidactuated member, said actuating member being movable by an applied forceto move its connected tab beyond an aligned position with both pivotmeans causing said toggle link to swing about its pivot means to aposition where said stop means engages the U'shaped portion of saidactuated member whereby the spring force transmitted to the movable endof said actuated member reversesits-direction with a snap action, andthe connecting portion ofsaid actuating member being operably secured tothe'ofisetting portion of said actuated member forming a flexible hingewhereby the movable end of said actuated member moveswith a wipingaction in response to the force applied to said actuating member.

12. In a snap acting mechanism, the combination comprising an actuatinglever and an actuated arm in superimposedrelation, means includingresilientmeans operatively connected between one pair of adjacent ends.of

said lever and said arm whereby movement of said lever causes. saidresilient means to pass a dead center position for moving said arm witha snap action in one direction, and means connecting the other pair'ofadjacent ends of said leverand said arm including a back-up plate havinga pairof horizontal portions offset from each other, a vertical portionextending from one of the horizontal portions and being secured to theother end of said lever,

the other end of said arm being secured to the other of the horizontalportions, and flexible mounting means for the said other end of saidlever whereby the movement of said lever causes said connecting means totransmit a force for moving said arm in another direction.

13. The combination as recited in claim 2 wherein the mounting end ofsaid actuated elementincludes a backup plate having a horizontalportion, and a return spring exerting a biasing force on said back-upplate and said actuated element.

14. The combination as recited in claim 13 wherein said actuatingelement is provided with a notched upper,

edge and a bridge member engages said notched upper edge to apply anoperating force to said actuating element.

15. The combination as recited in claim 13 wherein said actuatingelement is provided with a projection on its upper edge and a plungermember engages said projection to apply-an operating force to saidactuating element.

References Cited in the file of this patent I UNITED STATES PATENTS1,796,854 Mayer Oct. 16, 1934 2,418,068 Cornelius Mar. 25, 19472,508,040 Ransome May 16, 1950 2,537,682 Ljungfeldt Ian. 9, 19512,589,563 Miller Mar. 18, 1952- 2,651,690 Ra'ney Sept. 8, 19532,70t);079 Haydon Jan. 18, 1955 V FOREIGN PATENTS 985,620 France Mar.14, 1952

